Example

Imagine that Tennessee is having an election on the location of its capital. The population of Tennessee is concentrated around its four major cities, which are spread throughout the state. For this example, suppose that the entire electorate lives in these four cities and that everyone wants to live as near to the capital as possible.

The candidates for the capital are:

• Memphis, the state's largest city, with 42% of the voters, but located far from the other cities
• Nashville, with 26% of the voters, near the center of the state
• Knoxville, with 17% of the voters
• Chattanooga, with 15% of the voters

The preferences of the voters would be divided like this:

In FPTP, only the first preferences matter, and voters are allowed to mark only them on the ballot. As such, the votes would be counted as 42 per cent for Memphis, 26 for Nashville, 17 for Knoxville, and 15 for Chattanooga. Since Memphis has the most votes, it would win a FPTP election although the majority of voters would oppose it the most. In contrast, Condorcet methods would return Nashville – the actual capital of Tennessee – whereas instant-runoff voting would return Knoxville.

Voting method criteria

Scholars rate voting methods using mathematically derived voting method criteria, which describe desirable features of a method. No ranked preference method can meet all the criteria, because some of them are mutually exclusive, as shown by results such as Arrow's impossibility theorem and the Gibbard–Satterthwaite theorem.^[4]

The following criteria are passed or failed when FPTP is used in a single-winner contest:

	Name of criterion	Explanation/details
Y	Majority criterion	The majority criterion states that "if one candidate is preferred by a majority (more than 50%) of voters, then that candidate must win".[5] First-past-the-post meets this criterion (though not the converse: a candidate does not need 50% of the votes in order to win)
N	Mutual majority criterion	The mutual majority criterion states that "if a majority (more than 50%) of voters top-rank some k candidates, then one of those k candidates must win". First-past-the-post does not meet this criterion.[6]
N	Condorcet winner criterion	The Condorcet winner criterion states that "if a candidate would win a head-to-head competition against every other candidate, then that candidate must win the overall election". First-past-the-post does not[7] meet this criterion.
N	Condorcet loser criterion	The Condorcet loser criterion states that "if a candidate would lose a head-to-head competition against every other candidate, then that candidate must not win the overall election". First-past-the-post does not[7] meet this criterion.
N	Independence of irrelevant alternatives criterion	The independence of irrelevant alternatives criterion states that "the election outcome remains the same even if a candidate who cannot win decides to run." First-past-the-post does not meet this criterion.
N	Independence of clones criterion	The independence of clones criterion states that "the election outcome remains the same even if an identical candidate who is equally-preferred decides to run." First-past-the-post does not meet this criterion. This makes it vulnerable to spoilers.
Y	Monotonicity criterion
Y	Consistency criterion
Y	Participation criterion
N	Reversal symmetry	Reversal symmetry is a voting system criterion which requires that if candidate A is the unique winner, and each voter's individual preferences are inverted, then A must not be elected
Not applicable	Later-no-harm	Since plurality does not allow marking later preferences on the ballot at all, it is impossible to either harm or help a favorite candidate by marking later preferences, and so it trivially passes both Later-No-Harm and Later-No-Help. However, because it forces truncation, it shares some problems with methods that merely encourage truncation by failing Later-No-Harm. Similarly, though to a lesser degree, because it does not allow voters to distinguish between all but one of the candidates, it shares some problems with methods which fail Later-No-Help, which encourage voters to make such distinctions dishonestly.
Not applicable	Later-no-help

The following criteria are passed or failed when FPTP is used to elect legislatures in particular:

	Name of criterion	Explanation/details
N	No majority reversal	Although the majority criterion is met for each constituency vote, it is not met when adding up the total votes for a winning party in a parliament.
N	Proportional in theory
N	Proportional in practice
Y	Provides local representation	Standard implementation of single-member plurality is based on local districts

Party distribution

A graph showing the difference between the popular vote (inner circle) and the seats won by parties (outer circle) at the 2015 UK general election

Perhaps the most striking effect of FPTP is the fact that the number of a party's seats in a legislature has nothing to do with its vote count in an election, only in how those votes were geographically distributed. This has been a target of criticism for the method, many arguing that a fundamental requirement of an election system is to accurately represent the views of voters. FPTP often creates "false majorities" by over-representing larger parties (giving a majority of the parliamentary/legislative seats to a party that did not receive a majority of the votes) while under-representing smaller ones. In Canada, majority governments have been formed due to one party winning a majority of the votes cast in Canada only three times since 1921: in 1940, 1958 and 1984. In the United Kingdom, 19 of the 24 general elections since 1922 have produced a single-party majority government. In all but two of them (1931 and 1935), the leading party did not take a majority of the votes across the UK.

In extreme cases, this can lead to a party receiving the plurality or even majority of total votes but still lose in legislative seats. This results in a situation called a majority reversal or election inversion.^[9][10] Famous examples of the second placed party (in votes nationally) winning a majority of seats include the elections in Ghana in 2012, in New Zealand in 1978 and in 1981 and in the United Kingdom in 1951. Famous examples of the second placed party (in votes nationally) winning a plurality of seats include the election in Canada in 2019 and 2021. Even when a party wins more than half the votes in an almost purely two-party-competition, it is possible for the runner-up to win a majority of seats. This happened in Saint Vincent and the Grenadines in 1966, 1998 and 2020 and in Belize in 1993. This need not be a result of malapportionment. Even if all seats represent the same number of votes, the second placed party (in votes nationally) can win a majority of seats by efficient vote distribution. Winning seats narrowly and losing elsewhere by big margins is more efficient than winning seats by big margins and losing elsewhere narrowly. For a majority in seats, it is enough to win a plurality of votes in a majority of constituencies. Even with only two parties and equal constituencies, to win a majority of seats just requires receiving more than half the vote in more than half the districts—even if the other party receives all the votes cast in the other districts—so just over a quarter of the votes of the whole is theoretically enough for a majority in the legislature. Where multiple parties split the vote in a district, as few as 18 percent of the vote is enough to take a seat in FPTP.^[11][12] And where multiple parties win seats, a minority position in the legislature (a party with much less members than half of the assembly) could have the largest block in the chamber and be set in a commanding position, although still needing majority support to pass a bill.

Under first-past-the-post, a small party may draw votes and seats away from a larger party that it is more similar to, and therefore give an advantage to one it is less similar to. For example, in the 2000 United States presidential election, the left-leaning Ralph Nader drew more votes from the left-leaning Al Gore than his opponent, leading to accusations that Nader was a "spoiler" for the Democrats. According to the political pressure group Make Votes Matter, FPTP creates a powerful electoral incentive for large parties to target similar segments of voters with similar policies. The effect of this reduces political diversity in a country because the larger parties are incentivised to coalesce around similar policies.^[13] The ACE Electoral Knowledge Network describes India's use of FPTP as a "legacy of British colonialism".^[14]

Duverger's law is an idea in political science which says that constituencies that use first-past-the-post methods will lead to two-party systems, given enough time. Economist Jeffrey Sachs explains:

The main reason for America's majoritarian character is the electoral system for Congress. Members of Congress are elected in single-member districts according to the "first-past-the-post" (FPTP) principle, meaning that the candidate with the plurality of votes is the winner of the congressional seat. The losing party or parties win no representation at all. The first-past-the-post election tends to produce a small number of major parties, perhaps just two, a principle known in political science as Duverger's Law. Smaller parties are trampled in first-past-the-post elections.

— from Sachs's The Price of Civilization, 2011^[15]

However, most countries with first-past-the-post elections have multiparty legislatures (albeit with two parties larger than the others), the United States being the major exception.^[16] There is a counter-argument to Duverger's Law, that while on the national level a plurality system may encourage two parties, in the individual constituencies supermajorities will lead to the vote fracturing.^[17]

It has been suggested that the distortions in geographical representation provide incentives for parties to ignore the interests of areas in which they are too weak to stand much chance of gaining representation, leading to governments that do not govern in the national interest. Further, during election campaigns the campaigning activity of parties tends to focus on marginal seats where there is a prospect of a change in representation, leaving safer areas excluded from participation in an active campaign.^[18] Political parties operate by targeting districts, directing their activists and policy proposals toward those areas considered to be marginal, where each additional vote has more value.^[19][20][21]

This feature of FPTP has often been used by its supporters in contrast to proportional systems. In the latter, smaller parties act as 'kingmakers' in coalitions as they have greater bargaining power and therefore, arguably, their influence on policy is disproportional to their parliamentary size- this is largely avoided in FPTP systems where majorities are generally achieved.^[22] FPTP often produces governments which have legislative voting majorities,^[23] thus providing such governments the legislative power necessary to implement their electoral manifesto commitments during their term in office. This may be beneficial for the country in question in circumstances where the government's legislative agenda has broad public support, albeit potentially divided across party lines, or at least benefits society as a whole. However handing a legislative voting majority to a government which lacks popular support can be problematic where said government's policies favour only that fraction of the electorate that supported it, particularly if the electorate divides on tribal, religious, or urban–rural lines. There is also the perceived issue of unfair coalitions where a smaller party can form a coalition with other smaller parties and form a government, without a clear mandate as was the case in the 2009 Israeli legislative election where the leading party Kadima, was unable to form a coalition so Likud, a smaller party, managed to form a government without being the largest party. The use of proportional representation (PR) may enable smaller parties to become decisive in the country's legislature and gain leverage they would not otherwise enjoy, although this can be somewhat mitigated by a large enough electoral threshold. They argue that FPTP generally reduces this possibility, except where parties have a strong regional basis. A journalist at Haaretz noted that Israel's highly proportional Knesset "affords great power to relatively small parties, forcing the government to give in to political blackmail and to reach compromises";^[24][25] Tony Blair, defending FPTP, argued that other systems give small parties the balance of power, and influence disproportionate to their votes.^[26] Allowing people into parliament who did not finish first in their district was described by David Cameron as creating a "Parliament full of second-choices who no one really wanted but didn't really object to either."^[27] Winston Churchill criticized the alternative vote system as "determined by the most worthless votes given for the most worthless candidates."^[28]

FPTP often results in strategic voting which has prevented extreme left and right-wing parties from gaining parliamentary seats. For example, PR systems such as the electoral system of Hungary have seen Fidesz (right-wing, populist party) win 135 seats in the 2022 Hungarian parliamentary election and has remained the largest party in Hungary since 2010. Since 2010, Fidesz has implemented anti-democratic reforms that now mean the European Parliament no longer qualifies Hungary as a full democracy.^[29] On the other hand, the Constitution Society published a report in April 2019 stating that, "[in certain circumstances] FPTP can ... abet extreme politics, since should a radical faction gain control of one of the major political parties, FPTP works to preserve that party's position. ...This is because the psychological effect of the plurality system disincentivises a major party's supporters from voting for a minor party in protest at its policies, since to do so would likely only help the major party's main rival. Rather than curtailing extreme voices, FPTP today empowers the (relatively) extreme voices of the Labour and Conservative party memberships."^[30][31] Electoral reform campaigners have argued that the use of FPTP in South Africa was a contributory factor in the country adopting the apartheid system after the 1948 general election in that country.^[32][33] Leblang and Chan found that a country's electoral system is the most important predictor of a country's involvement in war, according to three different measures: (1) when a country was the first to enter a war; (2) when it joined a multinational coalition in an ongoing war; and (3) how long it stayed in a war after becoming a party to it.^[34][35] When the people are fairly represented in parliament, more of those groups who may object to any potential war have access to the political power necessary to prevent it. In a proportional democracy, war and other major decisions generally requires the consent of the majority.^[35][36][37] The British human rights campaigner Peter Tatchell, and others, have argued that Britain entered the Iraq War primarily because of the political effects of FPTP and that proportional representation would have prevented Britain's involvement in the war.^[38][39][40]

Tactical voting

To a greater extent than many others, the first-past-the-post method encourages "tactical voting". Voters have an incentive to vote for a candidate who they predict is more likely to win, as opposed to their preferred candidate who may be unlikely to win and for whom a vote could be considered as wasted. FPTP wastes fewer votes when it is used in two-party contests. But waste of votes and minority governments are more likely when large groups of voters vote for three, four or more parties as in Canadian elections. Canada uses FPTP and only two of the last seven federal Canadian elections (2011 and 2015) produced single-party majority governments. In none of them did the leading party receive a majority of the votes.

The position is sometimes summarised, in an extreme form, as "all votes for anyone other than the runner-up are votes for the winner."^[41] This is because votes for these other candidates deny potential support from the second-placed candidate, who might otherwise have won. Following the extremely close 2000 U.S. presidential election, some supporters of Democratic candidate Al Gore believed one reason he lost to Republican George W. Bush is that a portion of the electorate (2.7%) voted for Ralph Nader of the Green Party, and exit polls indicated that more of them would have preferred Gore (45%) to Bush (27%).^[42] This election was ultimately determined by the results from Florida, where Bush prevailed over Gore by a margin of only 537 votes (0.009%), which was far exceeded by the 97488 (1.635%) votes cast for Nader in that state.

In Puerto Rico, there has been a tendency for Independentista voters to support Populares candidates. This phenomenon is responsible for some Popular victories, even though the Estadistas have the most voters on the island, and is so widely recognised that Puerto Ricans sometimes call the Independentistas who vote for the Populares "melons", because that fruit is green on the outside but red on the inside (in reference to the party colors).

Because voters have to predict who the top two candidates will be, results can be significantly distorted:

• Some voters will vote based on their view of how others will vote as well, changing their originally intended vote;
• Substantial power is given to the media, because some voters will believe its assertions as to who the leading contenders are likely to be. Even voters who distrust the media will know that others do believe the media, and therefore those candidates who receive the most media attention will probably be the most popular;
• A new candidate with no track record, who might otherwise be supported by the majority of voters, may be considered unlikely to be one of the top two, and thus lose votes to tactical voting;
• The method may promote votes against as opposed to votes for. For example, in the UK (and only in the Great Britain region), entire campaigns have been organised with the aim of voting against the Conservative Party by voting Labour, Liberal Democrat in England and Wales, and since 2015 the SNP in Scotland, depending on which is seen as best placed to win in each locality. Such behaviour is difficult to measure objectively.

Proponents of other voting methods in single-member districts argue that these would reduce the need for tactical voting and reduce the spoiler effect. Examples include preferential voting systems, such as instant runoff voting, as well as the two-round system of runoffs and less tested methods such as approval voting and Condorcet methods. Wasted votes are seen as those cast for losing candidates, and for winning candidates in excess of the number required for victory. For example, in the UK general election of 2005, 52% of votes were cast for losing candidates and 18% were excess votes—a total of 70% "wasted" votes. On this basis a large majority of votes may play no part in determining the outcome. This winner-takes-all system may be one of the reasons why "voter participation tends to be lower in countries with FPTP than elsewhere."^[43]

Geography

The effect of a system based on plurality voting spread over many separate districts is that the larger parties, and parties with more geographically concentrated support, gain a disproportionately large share of seats, while smaller parties with more evenly distributed support gain a disproportionately small share. This is because in doing this they win many seats and do not 'waste' many votes in other areas. As voting patterns are similar in about two-thirds of the districts, it is more likely that a single party will hold a majority of legislative seats under FPTP than happens in a proportional system, and under FPTP it is rare to elect a majority government that actually has the support of a majority of voters. Because FPTP permits many wasted votes, an election under FPTP is more easily gerrymandered. Through gerrymandering, electoral areas are designed deliberately to unfairly increase the number of seats won by one party by redrawing the map such that one party has a small number of districts in which it has an overwhelming majority of votes (whether due to policy, demographics which tend to favour one party, or other reasons), and many districts where it is at a smaller disadvantage.

The British Electoral Reform Society (ERS) says that regional parties benefit from this system. "With a geographical base, parties that are small UK-wide can still do very well".^[44]

On the other hand, minor parties that do not concentrate their vote usually end up getting a much lower proportion of seats than votes, as they lose most of the seats they contest and 'waste' most of their votes.^[21]

The ERS also says that in FPTP elections using many separate districts "small parties without a geographical base find it hard to win seats".^[44]

Make Votes Matter said that in the 2017 general election, "the Green Party, Liberal Democrats and UKIP (minor, non-regional parties) received 11% of votes between them, yet they shared just 2% of seats", and in the 2015 general election, "[t]he same three parties received almost a quarter of all the votes cast, yet these parties shared just 1.5% of seats."^[45]

According to Make Votes Matter, in the 2015 UK general election UKIP came in third in terms of number of votes (3.9 million/12.6%), but gained only one seat in Parliament, resulting in one seat per 3.9 million votes. The Conservatives on the other hand received one seat per 34,000 votes.^[45]

The winner-takes-all nature of FPTP leads to distorted patterns of representation, since it exaggerates the correlation between party support and geography.

For example, in the UK the Conservative Party represents most of the rural seats in England, and most of the south of England, while the Labour Party represents most of the English cities and most of the north of England.^[46] This pattern hides the large number of votes for the non-dominant party. Parties can find themselves without elected politicians in significant parts of the country, heightening feelings of regionalism. Party supporters (who may nevertheless be a significant minority) in those sections of the country are unrepresented.

In the 2019 Canadian federal election Conservatives won 98% of the seats in Alberta and Saskatchewan with only 68% of the vote. The lack of non-Conservative representation gives the appearance of greater Conservative support than actually exists.^[47] Similarly, in Canada's 2021 elections, the Conservative Party won 88% of the seats in Alberta with only 55% of the vote, and won 100% of the seats in Saskatchewan with only 59% of the vote.^[48]

First-past-the-post within geographical areas tends to deliver (particularly to larger parties) a significant number of safe seats, where a representative is sheltered from any but the most dramatic change in voting behaviour. In the UK, the Electoral Reform Society estimates that more than half the seats can be considered as safe.^[49] It has been claimed that members involved in the 2009 expenses scandal were significantly more likely to hold a safe seat.^[50][51]

However, other voting systems, notably the party-list system, can also create politicians who are relatively immune from electoral pressure (especially when using a closed-list).

Criticism and replacement

People campaigning against first-past-the-post and in favour of proportional representation

Non-plurality voting systems have been devised since at least 1299, when Ramon Llull came up with both the Condorcet and Borda count methods, which were respectively reinvented in the 18th century by the Marquis de Condorcet and Jean-Charles de Borda. More serious investigation into electoral systems came in the late 18th century, when several thinkers independently proposed systems of proportional representation to elect legislatures. The single transferable vote in particular was invented in 1819 by Thomas Wright Hill, and first used in a public election in 1840 by his son Rowland for the Adelaide City Council in Australia. STV saw its first national use in Denmark in 1855, and was reinvented several times in the late 19th century.

The Proportional Representation Society was founded in England in 1884 and began campaigning. STV was used to elect the British House of Commons's university constituencies between 1918 and their abolition in 1950.

Many countries which use FPTP have active campaigns to switch to proportional representation (e.g. UK^[52] and Canada^[53]). Most modern democracies use forms of proportional representation.^[54] In the case of the UK, the campaign to get rid of FPTP has been ongoing since at least the 1970s.^[55] However, in both these countries, reform campaigners face the obstacle of large incumbent parties who control the legislature and who are incentivised to resist any attempts to replace the FPTP system that elected them on a minority vote.

Heads of state elected by FPTP

Legislatures elected exclusively by FPTP/SMP

The following is a list of countries currently following the first-past-the-post voting system for their national legislatures.^[56][57]

Use of FPTP/SMP in mixed systems for electing legislatures

The following countries use FPTP/SMP to elect part of their national legislature, in different types of mixed systems.

Alongside block voting (fully majoritarian systems) or as part of mixed-member majoritarian systems (semi-proportional representation)

As part of mixed-member proportional (MMP) or additional member systems (AMS)

Former use

• Argentina (The Chamber of Deputies uses party list PR. Only twice used FPTP, first between 1902 and 1905 used only in the elections of 1904,^[59] and the second time between 1951 and 1957 used only in the elections of 1951 and 1954.)^[60]
• Australia (replaced by IRV in 1918 for both the House of Representatives and the Senate, with STV being introduced to the Senate in 1948)
• Belgium (adopted in 1831, replaced by party list PR in 1899)—^[61] the Member of the European Parliament for the German-speaking electoral college is still elected by FPTP^[62]
• Cyprus (replaced by proportional representation in 1981)
• Denmark (replaced by proportional representation in 1920)
• Hong Kong (adopted in 1995, replaced by party list PR in 1998)
• Japan (replaced by parallel voting in 1993)
• Lebanon (replaced by proportional representation in June 2017)
• Lesotho (replaced by MMP Party list in 2002)
• Malta (replaced by STV in 1921)
• Mexico (replaced by parallel voting in 1977)
• Nepal (replaced by parallel voting)^[63]
• Netherlands (replaced by party list PR in 1917)^[64]
• New Zealand (replaced by MMP in 1996)
• Papua New Guinea (replaced by IRV in 2002)^[65]
• Philippines (replaced by parallel voting in 1998 for House of Representatives elections, and by multiple non-transferable vote in 1941 for Senate elections)
• Portugal (replaced by party list PR)^[66]
• Serbia (adopted in 1990, replaced by party list PR in 1992)^[67]
• South Africa (replaced by party list PR in 1994)
• Tanzania (replaced by parallel voting in 1995)